Over 30 million US adults and nearly 20% of primary care patients suffer from chronic insomnia. Chronic insomnia is associated with increased morbidity, mortality, and high economic costs, and thus represents a major public health problem. Importantly, the prevalence of insomnia is significantly higher in Hispanics (26.5%) than non-Hispanic Whites (22.5%), and this disparity is widening over time. Cognitive behavioral therapy for insomnia is a robustly effective psychological intervention for treatment of insomnia with sustained benefits, and is recommended over medications as the first-line treatment for chronic insomnia. Unfortunately, few receive this standard of care. Hispanics, and particularly those with limited English Proficiency, are even less likely than non-Hispanic Whites to have access to high quality evidence-based behavioral health care such as CBT-I, primarily because of the lack of available qualified bilingual behavioral providers trained to deliver CBT-I in Spanish and costs. Given the increasing prevalence of insomnia among Hispanics, and the linguistic realities of today's behavioral healthcare work force, the demand for bilingual behavioral health providers equipped to deliver CBT-I in Spanish significantly outweighs the supply. Advances in health information technology such as self-guided ehealth treatments represent an innovative and scalable means to address the supply and demand imbalance that perpetuate mental health care disparities, however its implementation in underserved communities remains elusive. In fact, CBT-I delivered via an online web-based platform is as effective as CBT-I delivered in-person, but extant ehealth programs of CBT-I have not been adapted for use among underserved patient populations. Further, data on the barriers and facilitators of implementation of these ehealth behavioral treatments in underserved racial/ethnic minority populations were rarely collected or used to support its integration in primary care. The proposed study will use a hybrid trial type 1 effectiveness-implementation study design and a mixed methods approach that leverages recent technological advances in ehealth platforms to (1) enroll 200 Spanish-speaking Hispanic primary care patients with chronic insomnia into an RCT that compares the effectiveness of a culturally adapted ehealth version of CBT-I with enhanced usual care on reduction of insomnia symptoms; (2) concurrently assess the organizational, patient, and provider barriers to implementation, and (3), determine the cost-effectiveness of the intervention. By leveraging recent advances in e-health and capitalizing on the increasing rates of Internet use among Hispanic US adults, this study has the potential to expand access to evidence-based alternatives to pharmacotherapy for the management of chronic insomnia, and to narrow existing racial/ethnic disparities in access to high quality behavioral health care for primary care patients.